﻿using System.Text;
using System.Windows;
using System.Windows.Controls;

namespace SamizdatSearch
{
  public static class PasswordHelper
  {
    public static readonly DependencyProperty PasswordProperty =
      DependencyProperty.RegisterAttached("Password",
                                          typeof(string), typeof(PasswordHelper),
                                          new FrameworkPropertyMetadata(string.Empty, OnPasswordPropertyChanged));

    public static readonly DependencyProperty AttachProperty =
      DependencyProperty.RegisterAttached("Attach",
                                          typeof(bool), typeof(PasswordHelper), new PropertyMetadata(false, Attach));

    private static readonly DependencyProperty IsUpdatingProperty =
      DependencyProperty.RegisterAttached("IsUpdating", typeof(bool),
                                          typeof(PasswordHelper));


    public static void SetAttach(DependencyObject dp, bool value)
    {
      dp.SetValue(AttachProperty, value);
    }

    public static bool GetAttach(DependencyObject dp)
    {
      return (bool)dp.GetValue(AttachProperty);
    }

    public static string GetPassword(DependencyObject dp)
    {
      return (string)dp.GetValue(PasswordProperty);
    }

    public static void SetPassword(DependencyObject dp, string value)
    {
      dp.SetValue(PasswordProperty, value);
    }

    private static bool GetIsUpdating(DependencyObject dp)
    {
      return (bool)dp.GetValue(IsUpdatingProperty);
    }

    private static void SetIsUpdating(DependencyObject dp, bool value)
    {
      dp.SetValue(IsUpdatingProperty, value);
    }

    private static void OnPasswordPropertyChanged(DependencyObject sender,
                                                  DependencyPropertyChangedEventArgs e)
    {
      var passwordBox = (PasswordBox)sender;
      passwordBox.PasswordChanged -= PasswordChanged;

      if (!GetIsUpdating(passwordBox))
      {
        passwordBox.Password = (string)e.NewValue;
      }
      passwordBox.PasswordChanged += PasswordChanged;
    }

    private static void Attach(DependencyObject sender,
                               DependencyPropertyChangedEventArgs e)
    {
      var passwordBox = sender as PasswordBox;

      if (passwordBox == null)
        return;

      if ((bool)e.OldValue)
      {
        passwordBox.PasswordChanged -= PasswordChanged;
      }

      if ((bool)e.NewValue)
      {
        passwordBox.PasswordChanged += PasswordChanged;
      }
    }

    private static void PasswordChanged(object sender, RoutedEventArgs e)
    {
      var passwordBox = (PasswordBox)sender;
      SetIsUpdating(passwordBox, true);
      SetPassword(passwordBox, passwordBox.Password);
      SetIsUpdating(passwordBox, false);
    }
  }
}